import axios from "axios";
import * as cheerio from "cheerio";
import * as querystring from "querystring";
import { SearchResult } from "../../src/lib/entities";
import { logger } from "../../src/lib/logger";

const _useragent_list = [
  "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:66.0) Gecko/20100101 Firefox/66.0",
  "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36",
  "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36",
  "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.0.0 Safari/537.36",
  "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36",
  "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36 Edg/111.0.1661.62",
  "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/111.0",
];

function get_useragent(): string {
  return _useragent_list[Math.floor(Math.random() * _useragent_list.length)];
}

async function _req(
  term: string,
  results: number,
  lang: string,
  country: string,
  start: number,
  proxies: any,
  timeout: number,
  tbs: string | undefined = undefined,
  filter: string | undefined = undefined,
) {
  const params = {
    q: term,
    num: results, // Number of results to return
    hl: lang,
    gl: country,
    start: start,
  };
  if (tbs) {
    params["tbs"] = tbs;
  }
  if (filter) {
    params["filter"] = filter;
  }
  try {
    const resp = await axios.get("https://www.google.com/search", {
      headers: {
        "User-Agent": get_useragent(),
      },
      params: params,
      proxy: proxies,
      timeout: timeout,
    });
    return resp;
  } catch (error) {
    if (error.response && error.response.status === 429) {
      throw new Error("Google Search: Too many requests, try again later.");
    }
    throw error;
  }
}

export async function googleSearch(
  term: string,
  advanced = false,
  num_results = 7,
  tbs = undefined as string | undefined,
  filter = undefined as string | undefined,
  lang = "en",
  country = "us",
  proxy = undefined as string | undefined,
  sleep_interval = 0,
  timeout = 5000,
): Promise<SearchResult[]> {
  let proxies: any = null;
  if (proxy) {
    if (proxy.startsWith("https")) {
      proxies = { https: proxy };
    } else {
      proxies = { http: proxy };
    }
  }

  // TODO: knowledge graph, answer box, etc.

  let start = 0;
  let results: SearchResult[] = [];
  let attempts = 0;
  const maxAttempts = 20; // Define a maximum number of attempts to prevent infinite loop
  while (start < num_results && attempts < maxAttempts) {
    try {
      const resp = await _req(
        term,
        num_results - start,
        lang,
        country,
        start,
        proxies,
        timeout,
        tbs,
        filter,
      );
      const $ = cheerio.load(resp.data);
      const result_block = $("div.g");
      if (result_block.length === 0) {
        start += 1;
        attempts += 1;
      } else {
        attempts = 0; // Reset attempts if we have results
      }
      result_block.each((index, element) => {
        const linkElement = $(element).find("a");
        const link =
          linkElement && linkElement.attr("href")
            ? linkElement.attr("href")
            : null;
        const title = $(element).find("h3");
        const ogImage = $(element).find("img").eq(1).attr("src");
        const description_box = $(element).find(
          "div[style='-webkit-line-clamp:2']",
        );
        const answerBox = $(element).find(".mod").text();
        if (description_box) {
          const description = description_box.text();
          if (link && title && description) {
            start += 1;
            results.push(new SearchResult(link, title.text(), description));
          }
        }
      });
      await new Promise((resolve) =>
        setTimeout(resolve, sleep_interval * 1000),
      );
    } catch (error) {
      if (error.message === "Too many requests") {
        logger.warn("Too many requests, breaking the loop");
        break;
      }
      throw error;
    }

    if (start === 0) {
      return results;
    }
  }
  if (attempts >= maxAttempts) {
    logger.warn("Max attempts reached, breaking the loop");
  }
  return results;
}
